Nonshrinkage cavity ingot mold



Se t. 1

p 927 w. F. M MAHON NONSHRINKAGE CAVITY INGOT MOLD v 2 Sheets-Sheet 1.

Filed June 10, 1925 n Q E WVE/WOA ATTORNEY Fig.2 V 95 Sept. 6,1927. 7 97 W. F. M MAHON NONSHRINKAGE' CAVITY INGOT MOLD Filed June 10, 1925 2 Sheets-Sheet 2 & 1

ATTORNEY Patented Sept. 7 6, 1927.,

N W S OFFICE.

WILLIAM FREDERICK MOMAHON, OF RIVERSIDE, CALIFQ:

NONSHBINGE CAVITY INGOT MOLD.

Application filed June 10, 1925. Serial No. 38,158.

This invention relates to new and useful improvements in molds for casting solid cylindrical ingots or alloy metal billets, and has articular reference to a compressed air evice for the same, the object of the invention being the production of a device of this character which will exert an air pressure upon the molten mass, the mold and also during the time of solidlfication, and thus prevent a shrink hole or cavity in the cast product.

Another object of the invention is to pro vide means whereby compressed air is delivered into a mold in a convenient and eflicient manner. While the invention is shown applied to molds for casting solid cylindrical ingots, it may obviously be used for any type of molds and used to equally good .advantage.

With these and other objects in view the invention resides and consists in the construction and novel combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawings and pointed out in the claims hereto appended, it being understood that various changes in the form, proportion, size and minor details of construction within the scope of the claims may be resorted to without departure from the spirit or sacrificing any of the advantages of the invention.

Similar characters of reference denote like corresponding parts throughout the several figures of the accompanying drawings formin a part of thisspecification, and upon w ich,

Figure 1 is a longitudinal sectional elevation, showing the general arrangement of an electric arc furnace and a mold in position to receive a charge" of molten metal, and also showing the compressed air reservoir and'an air piping system.

Figure 2 is a cross section of a solid cylindrical ingot or billet mold, on a larger scale, showing the compressed air device in a closed position. I

Figure 3 is a side elevation of Figure 2.

Referringv in detail to the character 'of reference marked upon the drawings, 1 rep resents an electric arc furnace, the principle of which is well known, in which metals are converted into a molten mass. The furnace is supported by bearings 11 which rest on a concrete foundation 27, and is turned on rollers 2, until the metal can pour out of the spout 3 into the mold 4 which is held Iion place directly inway of the flow of metal 3 As this method of melting ore and pouring same into molds is of standard construction and the principle well known, I shall theremeans of pedestal supporting arms 21.

fore describe only the parts pertaining to -my improvement, as all other description wouldbe superfluous.

Heretofore when the solid cylindrical mass of molten metal was solidifyin in the molds,

a large cavity of the shape 0 an elongated cone or volcanic crater would form in the upper end portion of the billet or ingot, this said cavity was caused by shrinkage action, when cooling, of the particular metal used in making the ingot or billet, and also because-of the-fact which I have discovered from actual research, and that is,'tha't because there is no constant pressure over the entire end area of the ingot to keep the upper outer diameter edge of the ingot from solidifyingbefore the center'does.

After the molten metal charge is poured into the billet mold 4, I swing my compressed air device 5 into a closed, air-tight position on the mold 4 and then turn on the compressed air, by means of air valve 6 that is incorporated in pipe line 7 from the com-- pressed air reservoir 8. Thus creating a constant evenly distributed pressure extending over the entire end portion of the molten mass in the mold, and thereby keeping the outer edge diameter of the ingot practically level with the center during the time of solidification and thus preventing a large pike or cavity in the upper end portion of the casting.

The compressed air reservoir 8 in this particular case isbnilded in the mold supporting pedestal 9 and is cylindrical in formation. I have provided an air pressure gau e 10 to record the pressure of the air int e reservoir 8 and a relief valve 12 to release the air at any specified ressure, both the air pressure gauge 10 an the relief valve 12 are standard commercial articles, the construction' and principle of which are well known. V

Pipe line 13 serves to provide means for transporting the compressed air from exsquare lu voir 8.

My so-called compressed air device is supported by a yoke 14: which has two de nd-- mg arms 15, each arm having a roun end portion with a hole in it to provide a. hinge movement for it, on shoulder studs 16, that have threaded engagement with mold 4. Centrally between the two arms 15 in the yoke 14 is also provided a threaded hub 17- for engagement with spindle 18.

' Spindle 18 serves to attach the air chamber cap 19 with the yoke 14, and it is a round threaded shaft havin threaded en gagement with yoke 14, an portion upset to engage the air chamber cap 19, andthe other end ortion havin a and a threade end to hol a handwhee 20, it can be readily seen that blyl turning the handwheel 20 in one direction t 's action will in turnthrough the screw principle, due to the threaded relation of the yoke 14' andthe spindle 18, create a reaction through'yoke 14.- which is held by shoulder studs 16 to-the mold 4, and will thereby force the air chamber cap -19 down on the ca receiver '22. The air chamber cap 19 an the cap receiver-22 are of'male and female joint construction, and therefore insure an airtight connection. 1

'The air chamber cap 19 is a cylindrical cup shaped formation having at its u er end portion an extending hub 23 w ich serves to providemeans for connecting the spindle 18 with same.

The spindle 18 is held in this hub b a filler cap 24 that bears on the upset en of the spindle 18 and has threaded engagement with the: said hub 23. The other end portion of the air chamber cap 19 is open substantially for the full diameter of the air chamber 24, and has a sealing indentation on the outer rim 25. for making an air-tight connection with the cap receiver 22. A pipe tap 26 is provided in the air chamber cap 19.

for the compressed air pipe 7 connection,

to admit the said compressed 'air from an air reservoir.

The cap receiver 22 is a hollow circular disc plate and is fastened on one side by fiat head screws 28 to the mold 4. a The spacing of the flat head screws 28 will be 7 'such as to insure an air-tight joint. On. the

other side of the cap receiver 22' I have provided a V shaped rim 23 so as to make a male connection with the air'chamber cap 19. I have also provided a steep inclination on the inner diameter so as to prevent any metal or dirt lodging there to hinder makin a quick air-tight joint.

andwheel 20 serves to transmit force to the spindle 18 and is circular in formation havin a round outer rim 24 that is connecte b spokes with a round central hub 25, ub has a square hole in its center with one endto engage with'spindle' 18. Nut 26 serves to prevent the handwheel- 20 from coming 016: the spindle 18.

To remove the billet from the mold 4, unscrew the handwheel 20 until the air chamber cap 19 is clear of the cap receiver 22 and the entire compressed air device 5 hinges on shoulder studs 16 can be swung clear of the end of the mold 4 allowing thereby the in 0t or billet to have free access from the mol 4.

Having thus described my invention, what I claim and desire to secure by Letters Pat-' ent 1s: 1

1. In a device for casting ingots, a pedestal, a mold open at its upper end, a mold support mounted on the pedestal to swing the mold as a whole to and from the pouring position, means for sealing the open end of the mold and movable with said support, and means for feeding a gas under pressure to the upper end of the mold.

2. In a device for casting ingots a pedestal, a mold support mounted on sai edestal to turn about an upright axis, an a plurality of molds carried by said sup ort and each movable as a whole to and pouring position by turning said support, a plurality of sealing closures for the molds movable with said support, and means for feeding gas under pressure to the upper ends of the molds.

3. In a device for casting ingots, a pedestal comprising a fluid pressure tank, a mold support mounted to swing on said pedestal, a mold carried by the support and shiftable as a whole about said pedestal by movement of said support, a sealing closure for the mold, and a valve controlled connection from the tank to the mold. I

4. In a device for casting ingots, a pedestal comprising a fluid pressure tank having an external bearing, a mold support mounted to turn about the tank on said bearing,.one or more molds mounted on said support and arranged to be carried thereby when in assembled condition to and from the pouring position, a sealing closure of the molds, and valve controlled conduits from the tank to the molds.

5. In a device for casting ingots, a mold having a pouring opening at the top provided with tapered walls about said opemng, a yoke pivoted to the mold, a closure carried by the yoke having tapered walls to fit those of the mold, means carried by the yoke for clamping the closure to the mold with said tapered 'walls in engagement to make a tight rom the closure, and a conduit leading to the interior 7 of the mold to conduct a fluid under pressure thereto.

6. In a device for casting ingots, a mold havin a pouring opening at the top thereof inclined wall to fit the tapered wall of the mold, means for clamping the closure to the mold, and a. valve controlled conduit leading through the closure to the space therein.

7 In a device for casting ingots, a. tank, a. pedestal, a mold support mounted to move on said pedestal, a mold carried by the sup I port, a sealing closure for the mold, and a valve controlled conduit from the tank to the mold.

In testimony thereof I have hereunto subscribed my name.

' WILLIAM FREDERICK McMAHON. 

